Put in a general fix for #219 - Handling input from zle -U

Depends on patch to ZSH from workers/40702:

  http://www.zsh.org/mla/workers/2017/msg00414.html

zsh-autosuggestions.zsh

@@ -293,6 +293,9 @@ _zsh_autosuggest_clear() {
 _zsh_autosuggest_modify() {
 	local -i retval
 
+	# Only added to zsh very recently
+	local -i KEYS_QUEUED_COUNT
+
 	# Save the contents of the buffer/postdisplay
 	local orig_buffer="$BUFFER"
 	local orig_postdisplay="$POSTDISPLAY"
@@ -304,6 +307,11 @@ _zsh_autosuggest_modify() {
 	_zsh_autosuggest_invoke_original_widget $@
 	retval=$?
 
+	# Don't fetch a new suggestion if there's more input to be read immediately
+	if [[ $PENDING > 0 ]] || [[ $KEYS_QUEUED_COUNT > 0 ]]; then
+		return $retval
+	fi
+
 	# Optimize if manually typing in the suggestion
 	if [ $#BUFFER -gt $#orig_buffer ]; then
 		local added=${BUFFER#$orig_buffer}